Artificial tooth and backing therefor



March 15,1932. 5, MYERS 1,849,686

ARTIFICIAL TEETH AND BACKING THEREFOR Filed Oct. 5, 1928 fiweywm": 54mmWarsaw. @W M.

Patented Mar. 15, 1932 PATENT OFFICE SIMON MYERSON, 0F CAMBRIDGE,MASSACHUSETTS ARTIFICIAL TOOTH AND BACKING THEREFOR Application filedOctober 5,

This invention relates more particularly to an artificial tooth of thepontic type adapted to replace a lost natural tooth, the body of thetooth being provided with a pin or pins projecting from its posteriorface adjacent a shoulder overhanging said face and adapted to entersockets in a metallic backing engaged with a portion of a bridge.

Pontic teeth with projecting pins are in extensive use. Heretofore,however, the relative arrangement of the pins, the backing sockets andthe shoulder has been such that the projecting portions of the pins areliable to interfere with the proper occlusion of the opposing teeth and,particularly, in that class of occluison known as short bite. Thiscondition often involves back teeth as well as front, the opposing teethin this class striking the pins or backing sockets before the teeth arein complete occlusion.

The object of'the invention is to obviate this objection and to furtherstrengthen the tooth by placing the pins in a stronger cross section ofthe tooth.

These and other objects are obtained by the improved constructionshereinafter described.

Of the accompanying drawings forming a part of this specification-Figure 1 is an inner side view of a tooth body and its pins, constructedin accordance with the invention.

Figure 2 is a section on line 22 of Figure 1.

Figure 3 is an inner side View, showing the body as in Figures 1 and 2,and a backing constructed in accordance with the invention.

Figure 4 is a section on line 41 of Figure 3.

Figure 5 is a view similar to Figure 4;, showing the wing portion of thebacking as it appears in the completed tooth.

Figure 6 is a perspective view of the backing to fit the tooth formshown by Figure 1.

Figure 7 is a section on line 77 of Figure 6.

1928. Serial No. 310,562.

Figure 8 is a view similar to Figure 5, showing a different form of thegingival portion of the tooth body, and a portion of a bridge.

Figure 9 is a view similar to Figure 1, showing a modification.

Figure 10 is a lingual perspective view of a backing designed to fit thetooth form shown by Figure 9.

Figure 11 is a labial perspective view of the backing shown by Figure 1.

Figure 12 is a side view of a tooth showing a difierent relativearrangement of the posterior face, the shoulder and its offset portionand the pins.

The same reference characters indicate the same parts in all of thefigures.

In the drawings, 12 designates a tooth body having a shoulder 16overhanging the posterior face 13 of the body. Pins 14 are embedded inthe body and project from the posterior face thereof. I have modifiedthe form of the shoulder by offsetting its midlength portion 15 from itsend portions 16, to

provide a recess within the shoulder, as shown by Figures 1 and 9.

The projecting portions of the pins 1 1 are preferably in closeproximity to the offset portion 15 and the pins are separated from saidportion by a narrow space, best shown by Figuresl and 2.

My invention includes an angular metallic backing having a facingportion 17, formed to bear on and be cemented to the posterior face 13and a wing portion 18, formed to bear on the body shoulder 16.

The backing is provided with sockets 19, arranged to receive pins 14,said sockets being preferably integral with the backing and formedthereon in any suitable manner, so that they have open inner ends andclosed outer ends, as best shown by Figure 7. Portions of the socketwalls projectfrom the wing portion 18, and are formed to be in terposedbetween the pins and the ofiset portion 15 of the shoulder.

The oli'set portion of the shoulder may be formed in two parts 15a, asshown by Figure 9.

In practice, a portion of the outer edge of the backing wing 18 isupset, as indicated at 21 (Figures 5 and 8) to close any crevice whichmay be formed between the ofiset portion 15 of the shoulder and the wingportion 18. This operation may be performed after the parts areassembled. A portion 23 of a bridge is shown by Figure 8.

The tooth body may have the usual root tip 2 k, or saddle tip 25, shownby Figures 8 and 12.

Neither the number of pins nor their shape or exact position in theshoulder depression will affect the principles of this invention. Theshoulder 16 may be perpendicular to the posterior face 13, or at anypreferred angle. I prefer a slightly obtuse angle of the shoulder to theposterior face with the offset nortion 15 approximately parallel to thelong axis of the pins, as shown by Figure 12. It will be seen thatportions of the sockets 19 are formed to enter and bear on the wall ofthe recess 15 or 1560, so that the sockets are interengaged with arecessed shoulder portion of the body to resist pressure tending todisplace the body edgewise or toward either the right or the left asviewed in Figure 3.

I claim:

1. An artificial tooth body having a shoulder overhanging its posteriorface, and a recess whereby a portion of the shoulder is offset, and pinsembedded in the posterior face of the tooth body in line with saidrecess and projecting from said face into the recessed portion and inclose proximity to the offset portion of the shoulder, thereby shortening the bite.

2. An artificial tooth body having a shoulder overhanging its posteriorface, and a recess whereby a portion of the shoulder is offset, and pinsembedded in that portion of the posterior face of the tooth body that iswithin the said recess and projecting from said face in proximity to thesaid offset portion of the shoulder.

3. An artificial tooth comprising a body having a shoulder overhangingits posterior face, and a recess in said. shoulder whereby a portion ofthe shoulder is offset, and pins embedded in the posterior face of thebody and projecting from said face in line with said recess and havingan annular backing provided with a facing portion formed to bear on saidposterior face, and a wing portion formed to bear on said shoulder andsaid recess, that portion of the wing bearing on said recess havingsockets adapted to receive said pins.

4. An angular backing having a facing portion formed to bear on theposterior face of a tooth body, and a wing portion formed to bear on ashoulder overhanging the posterior face, said wing portion having acentral thickened portion adapted to engage a recess upon the saidoverhanging shoulder, and sockets in the thickened central portion ofthe wing adapted to receive pins projecting rearwardly from saidposterior face.

In testimony whereof I have affixed my signature.

SIMON MYERSON.

